diff --git a/glass-easel-miniprogram-adapter/src/backend.ts b/glass-easel-miniprogram-adapter/src/backend.ts
index d0e8970..a0aea43 100644
--- a/glass-easel-miniprogram-adapter/src/backend.ts
+++ b/glass-easel-miniprogram-adapter/src/backend.ts
@@ -1,6 +1,7 @@
 import * as glassEasel from 'glass-easel'
-import { MiniProgramEnv, StyleIsolation } from '.'
-import { CodeSpace } from './space'
+import { type MiniProgramEnv } from './env'
+import { type CodeSpace } from './space'
+import { StyleIsolation } from './types'
 
 /**
  * A backend context that has been associated to an environment
diff --git a/glass-easel-miniprogram-adapter/src/behavior.ts b/glass-easel-miniprogram-adapter/src/behavior.ts
index eb08946..c01f492 100644
--- a/glass-easel-miniprogram-adapter/src/behavior.ts
+++ b/glass-easel-miniprogram-adapter/src/behavior.ts
@@ -1,6 +1,6 @@
-import * as glassEasel from 'glass-easel'
-import { GeneralComponentDefinition, utils as typeUtils } from './types'
-import { GeneralComponent } from './component'
+import type * as glassEasel from 'glass-easel'
+import { type GeneralComponentDefinition, type utils as typeUtils } from './types'
+import { type GeneralComponent } from './component'
 
 type DataList = typeUtils.DataList
 type PropertyList = typeUtils.PropertyList
diff --git a/glass-easel-miniprogram-adapter/src/component.ts b/glass-easel-miniprogram-adapter/src/component.ts
index aeb2327..e14cddc 100644
--- a/glass-easel-miniprogram-adapter/src/component.ts
+++ b/glass-easel-miniprogram-adapter/src/component.ts
@@ -1,6 +1,6 @@
 import * as glassEasel from 'glass-easel'
-import { utils as typeUtils } from './types'
-import { ComponentType, GeneralBehavior, TraitBehavior } from './behavior'
+import { type utils as typeUtils } from './types'
+import { type ComponentType, type GeneralBehavior, type TraitBehavior } from './behavior'
 import { SelectorQuery } from './selector_query'
 import { IntersectionObserver } from './intersection'
 import { MediaQueryObserver } from './media_query'
diff --git a/glass-easel-miniprogram-adapter/src/env.ts b/glass-easel-miniprogram-adapter/src/env.ts
new file mode 100644
index 0000000..ab3a6de
--- /dev/null
+++ b/glass-easel-miniprogram-adapter/src/env.ts
@@ -0,0 +1,73 @@
+import * as glassEasel from 'glass-easel'
+import { AssociatedBackend } from './backend'
+import { CodeSpace } from './space'
+
+/**
+ * A mini-program API environment
+ *
+ * Each environment manages multiple backend contexts.
+ * However, a backend context should be exclusively managed by a single environment
+ * (to avoid `StyleScopeId` confliction).
+ * It is able to create multiple `CodeSpace` within the environment.
+ */
+export class MiniProgramEnv {
+  private codeSpaceMap: { [id: string]: CodeSpace }
+  private globalCodeSpace: CodeSpace
+
+  /**
+   * Create an empty mini-program API environment
+   */
+  constructor() {
+    this.codeSpaceMap = Object.create(null) as { [id: string]: CodeSpace }
+    this.globalCodeSpace = new CodeSpace(this, false, {})
+  }
+
+  /**
+   * Get a global code space in which global components can be defined
+   *
+   * External glass-easel based components can be defined in this code space.
+   * All global components should be defined before any other `CodeSpace` created!
+   */
+  getGlobalCodeSpace(): CodeSpace {
+    return this.globalCodeSpace
+  }
+
+  /**
+   * Associate a backend context
+   *
+   * If `backendContext` is not given, the DOM-based backend is used
+   * (causes failure if running outside browsers).
+   * The backend context SHOULD NOT be associated by other environments!
+   */
+  associateBackend(backendContent?: glassEasel.GeneralBackendContext): AssociatedBackend {
+    const ctx = backendContent ?? new glassEasel.CurrentWindowBackendContext()
+    return new AssociatedBackend(this, ctx)
+  }
+
+  /**
+   * Create a component space that can manage WXML, WXSS, JS and static JSON config files
+   *
+   * The space can be specified as a *main* space.
+   * This makes some features available:
+   * * the `app.wxss` will be used as a style sheet for all root components in the space;
+   * * the `StyleIsolation.Shared` is accepted for components in the space.
+   * Non-main spaces usually act as plugins.
+   * `publicComponents` is a map for specifying a map of aliases and component paths.
+   */
+  createCodeSpace(
+    id: string,
+    isMainSpace: boolean,
+    publicComponents = Object.create(null) as { [alias: string]: string },
+  ): CodeSpace {
+    const cs = new CodeSpace(this, isMainSpace, publicComponents, this.globalCodeSpace)
+    this.codeSpaceMap[id] = cs
+    return cs
+  }
+
+  /**
+   * Get a component space by the `id` specified when created
+   */
+  getCodeSpace(id: string): CodeSpace | undefined {
+    return this.codeSpaceMap[id]
+  }
+}
diff --git a/glass-easel-miniprogram-adapter/src/index.ts b/glass-easel-miniprogram-adapter/src/index.ts
index f3c98c6..9ebc5fd 100644
--- a/glass-easel-miniprogram-adapter/src/index.ts
+++ b/glass-easel-miniprogram-adapter/src/index.ts
@@ -1,80 +1,6 @@
-import * as glassEasel from 'glass-easel'
-import { AssociatedBackend } from './backend'
-import { CodeSpace } from './space'
-
 export * as glassEasel from 'glass-easel'
-export * as types from './types'
-export { StyleIsolation } from './types'
-export * from './space'
 export { AssociatedBackend, Root } from './backend'
 export * as component from './component'
-
-/**
- * A mini-program API environment
- *
- * Each environment manages multiple backend contexts.
- * However, a backend context should be exclusively managed by a single environment
- * (to avoid `StyleScopeId` confliction).
- * It is able to create multiple `CodeSpace` within the environment.
- */
-export class MiniProgramEnv {
-  private codeSpaceMap: { [id: string]: CodeSpace }
-  private globalCodeSpace: CodeSpace
-
-  /**
-   * Create an empty mini-program API environment
-   */
-  constructor() {
-    this.codeSpaceMap = Object.create(null) as { [id: string]: CodeSpace }
-    this.globalCodeSpace = new CodeSpace(this, false, {})
-  }
-
-  /**
-   * Get a global code space in which global components can be defined
-   *
-   * External glass-easel based components can be defined in this code space.
-   * All global components should be defined before any other `CodeSpace` created!
-   */
-  getGlobalCodeSpace(): CodeSpace {
-    return this.globalCodeSpace
-  }
-
-  /**
-   * Associate a backend context
-   *
-   * If `backendContext` is not given, the DOM-based backend is used
-   * (causes failure if running outside browsers).
-   * The backend context SHOULD NOT be associated by other environments!
-   */
-  associateBackend(backendContent?: glassEasel.GeneralBackendContext): AssociatedBackend {
-    const ctx = backendContent ?? new glassEasel.CurrentWindowBackendContext()
-    return new AssociatedBackend(this, ctx)
-  }
-
-  /**
-   * Create a component space that can manage WXML, WXSS, JS and static JSON config files
-   *
-   * The space can be specified as a *main* space.
-   * This makes some features available:
-   * * the `app.wxss` will be used as a style sheet for all root components in the space;
-   * * the `StyleIsolation.Shared` is accepted for components in the space.
-   * Non-main spaces usually act as plugins.
-   * `publicComponents` is a map for specifying a map of aliases and component paths.
-   */
-  createCodeSpace(
-    id: string,
-    isMainSpace: boolean,
-    publicComponents = Object.create(null) as { [alias: string]: string },
-  ): CodeSpace {
-    const cs = new CodeSpace(this, isMainSpace, publicComponents, this.globalCodeSpace)
-    this.codeSpaceMap[id] = cs
-    return cs
-  }
-
-  /**
-   * Get a component space by the `id` specified when created
-   */
-  getCodeSpace(id: string): CodeSpace | undefined {
-    return this.codeSpaceMap[id]
-  }
-}
+export { MiniProgramEnv } from './env'
+export * from './space'
+export * as types from './types'
diff --git a/glass-easel-miniprogram-adapter/src/intersection.ts b/glass-easel-miniprogram-adapter/src/intersection.ts
index 17deaa3..b775425 100644
--- a/glass-easel-miniprogram-adapter/src/intersection.ts
+++ b/glass-easel-miniprogram-adapter/src/intersection.ts
@@ -1,5 +1,5 @@
-import * as glassEasel from 'glass-easel'
-import { GeneralComponent } from './component'
+import type * as glassEasel from 'glass-easel'
+import { type GeneralComponent } from './component'
 
 export type IntersectionObserverMargins = {
   left: number
diff --git a/glass-easel-miniprogram-adapter/src/media_query.ts b/glass-easel-miniprogram-adapter/src/media_query.ts
index 114d6c9..44e34f3 100644
--- a/glass-easel-miniprogram-adapter/src/media_query.ts
+++ b/glass-easel-miniprogram-adapter/src/media_query.ts
@@ -1,5 +1,5 @@
-import * as glassEasel from 'glass-easel'
-import { GeneralComponent } from './component'
+import type * as glassEasel from 'glass-easel'
+import { type GeneralComponent } from './component'
 
 export class MediaQueryObserver {
   private _$comp: GeneralComponent
diff --git a/glass-easel-miniprogram-adapter/src/selector_query.ts b/glass-easel-miniprogram-adapter/src/selector_query.ts
index 092e752..0545089 100644
--- a/glass-easel-miniprogram-adapter/src/selector_query.ts
+++ b/glass-easel-miniprogram-adapter/src/selector_query.ts
@@ -301,7 +301,7 @@ export class SelectorQuery {
               ],
               () => {
                 if (fields.properties) {
-                  if (elem instanceof glassEasel.Component) {
+                  if (glassEasel.Component.isComponent(elem)) {
                     fields.properties.forEach((propName) => {
                       if (glassEasel.Component.hasProperty(elem, propName)) {
                         const ds = elem.getComponentOptions().propertyPassingDeepCopy
diff --git a/glass-easel-miniprogram-adapter/src/space.ts b/glass-easel-miniprogram-adapter/src/space.ts
index ea071c0..f9860d1 100644
--- a/glass-easel-miniprogram-adapter/src/space.ts
+++ b/glass-easel-miniprogram-adapter/src/space.ts
@@ -1,25 +1,25 @@
 /* eslint-disable @typescript-eslint/no-unsafe-return */
 
 import * as glassEasel from 'glass-easel'
-import { MiniProgramEnv } from '.'
-import {
-  ComponentStaticConfig,
-  ComponentDefinitionOptions,
-  StyleIsolation,
-  BehaviorDefinition,
-  ComponentDefinition,
-  PageDefinition,
-  utils as typeUtils,
-} from './types'
-import { guid } from './utils'
 import {
   Behavior,
   ComponentType,
-  DefinitionFilter,
-  GeneralBehavior,
   TraitBehavior,
+  type DefinitionFilter,
+  type GeneralBehavior,
 } from './behavior'
-import { AllData, Component, ComponentProto, GeneralComponent } from './component'
+import { ComponentProto, type AllData, type Component, type GeneralComponent } from './component'
+import { type MiniProgramEnv } from './env'
+import {
+  StyleIsolation,
+  type BehaviorDefinition,
+  type ComponentDefinition,
+  type ComponentDefinitionOptions,
+  type ComponentStaticConfig,
+  type PageDefinition,
+  type utils as typeUtils,
+} from './types'
+import { guid } from './utils'
 
 // The page constructor
 export interface PageConstructor {
@@ -1123,7 +1123,7 @@ export class BehaviorBuilder<
     TNewData extends DataList = Empty,
     TNewProperty extends PropertyList = Empty,
     TNewMethod extends MethodList = Empty,
-    TNewComponentExport = never
+    TNewComponentExport = never,
   >(
     def: BehaviorDefinition<TNewData, TNewProperty, TNewMethod, TNewComponentExport> &
       ThisType<
diff --git a/glass-easel-miniprogram-adapter/src/types.ts b/glass-easel-miniprogram-adapter/src/types.ts
index c2431f1..4b3687d 100644
--- a/glass-easel-miniprogram-adapter/src/types.ts
+++ b/glass-easel-miniprogram-adapter/src/types.ts
@@ -1,6 +1,6 @@
-import { DeepCopyKind, typeUtils as utils } from 'glass-easel'
-import type { DefinitionFilter, GeneralBehavior, Behavior } from './behavior'
-import { GeneralComponent } from './component'
+import { type DeepCopyKind, type typeUtils as utils } from 'glass-easel'
+import type { Behavior, DefinitionFilter, GeneralBehavior } from './behavior'
+import { type GeneralComponent } from './component'
 
 export { typeUtils as utils } from 'glass-easel'
 
diff --git a/glass-easel-miniprogram-adapter/tests/base/env.ts b/glass-easel-miniprogram-adapter/tests/base/env.ts
index ee5c5f3..3b398ed 100644
--- a/glass-easel-miniprogram-adapter/tests/base/env.ts
+++ b/glass-easel-miniprogram-adapter/tests/base/env.ts
@@ -1,7 +1,7 @@
 /* eslint-disable no-new-func */
 /* eslint-disable @typescript-eslint/no-implied-eval */
 
-import * as glassEasel from 'glass-easel'
+import type * as glassEasel from 'glass-easel'
 import { TmplGroup } from 'glass-easel-template-compiler'
 
 export const tmpl = (src: string): glassEasel.template.ComponentTemplate => {
diff --git a/glass-easel-miniprogram-adapter/tests/space.test.ts b/glass-easel-miniprogram-adapter/tests/space.test.ts
index b1c8a69..812cfd2 100644
--- a/glass-easel-miniprogram-adapter/tests/space.test.ts
+++ b/glass-easel-miniprogram-adapter/tests/space.test.ts
@@ -1,12 +1,6 @@
 import * as glassEasel from 'glass-easel'
+import { type BehaviorConstructor, type ComponentConstructor, MiniProgramEnv, types } from '../src'
 import { tmpl } from './base/env'
-import {
-  MiniProgramEnv,
-  StyleIsolation,
-  BehaviorConstructor,
-  ComponentConstructor,
-  types,
-} from '../src'
 
 const domHtml = (elem: glassEasel.Element): string => {
   const domElem = elem.getBackendElement() as unknown as Element
@@ -430,7 +424,7 @@ describe('define', () => {
     codeSpace.addStyleSheet('child/comp', 'empty-style-sheet', 'child-comp')
     codeSpace.addComponentStaticConfig('child/comp', {
       component: true,
-      styleIsolation: StyleIsolation.Shared,
+      styleIsolation: types.StyleIsolation.Shared,
     })
     codeSpace.addCompiledTemplate(
       'child/comp',
@@ -451,7 +445,7 @@ describe('define', () => {
       usingComponents: {
         child: '/child/comp',
       },
-      styleIsolation: StyleIsolation.PageShared,
+      styleIsolation: types.StyleIsolation.PageShared,
     })
     codeSpace.addCompiledTemplate(
       'path/to/comp',
@@ -478,7 +472,7 @@ describe('define', () => {
     codeSpace.addStyleSheet('child/comp', 'empty-style-sheet', 'child-comp')
     codeSpace.addComponentStaticConfig('child/comp', {
       component: true,
-      styleIsolation: StyleIsolation.ApplyShared,
+      styleIsolation: types.StyleIsolation.ApplyShared,
     })
     codeSpace.addCompiledTemplate(
       'child/comp',
@@ -499,7 +493,7 @@ describe('define', () => {
       usingComponents: {
         child: '/child/comp',
       },
-      styleIsolation: StyleIsolation.PageApplyShared,
+      styleIsolation: types.StyleIsolation.PageApplyShared,
     })
     codeSpace.addCompiledTemplate(
       'path/to/comp',
@@ -528,7 +522,7 @@ describe('define', () => {
     codeSpace.addStyleSheet('child/comp', 'empty-style-sheet', 'child-comp')
     codeSpace.addComponentStaticConfig('child/comp', {
       component: true,
-      styleIsolation: StyleIsolation.Isolated,
+      styleIsolation: types.StyleIsolation.Isolated,
     })
     codeSpace.addCompiledTemplate(
       'child/comp',
@@ -549,7 +543,7 @@ describe('define', () => {
       usingComponents: {
         child: '/child/comp',
       },
-      styleIsolation: StyleIsolation.PageIsolated,
+      styleIsolation: types.StyleIsolation.PageIsolated,
     })
     codeSpace.addCompiledTemplate(
       'path/to/comp',
@@ -627,7 +621,7 @@ describe('define', () => {
       usingComponents: {
         child: '/child/comp',
       },
-      styleIsolation: StyleIsolation.PageIsolated,
+      styleIsolation: types.StyleIsolation.PageIsolated,
     })
     codeSpace.addCompiledTemplate(
       'path/to/comp',